Sound record for talking machines



New. 22, W. RAB LD 2,137,307

SOUND RECORD FOR TALKING MACHINES Filed March 3, 1934 Patented Nov. 22, 1938 UNl'lED STATES SOUND RECORD FOR. TALKING MACHINES Willy Rabald, Leipzig, Germany Application March 3, 1934, Serial No. 713,834 I In Germany March 3, 1933 2 Claims.

This invention relates to a special construction of sound records to be employed on one side or on both sides for recording and reproducing sound of all kinds, and the'novelty of which consists in that as sound wave carrier cadmium metal is employed which is applied in a layer of suitable thickness on a flexible plate serving as carrier for the cadmium layer and made of metal or other substances suitable therefor.

10 The accompanying drawing shows in elevation, a sound record. Referring more in detail to the accompanying drawing, there is illustrated a layer I of suitable'thickness of cadmium metal that is applied to a flexible plate 2 made of metal or other material suitable to act asa carrier for the cadmium metal.

A greatadvantage of cadmium consists in its a good cutting capability, which, as experiments have shown, is possible with no other metal whilst 20 obtaining the same advantages.

As compared with the pressing of record grooves in the metal the cutting thereof enables a higher tone frequency because the pressing requires a much higher recording pressure.

The'crystalline properties of cadmiumand the mirror-smooth tone grooves produced thereby reduce the recording noises to a minimum as compared with pressed plates. In known records made of metal or other material and serving for 5 direct recording and reproduction, a' preliminary or subsequent treatment is mostly necessary which is eliminated in case of the record according to the invention.

Cadmium is extremely resistant against atmos- 10 pheric influences, and possesses a hardness which is sufiicient for sound records to play them as often as desired. with a suitable needle of horn or wood.

1. A sound record, for use in recording and reproducing sound, which presents a material comprising cadmium as a sound I'BOOIdil .greproducing medium.

2. A sound record, for use in recording and 20 reproducing sound, which presents cadmium as sound recording-reproducing medium.

WILLY RABALD. 

